Ink jet printhead with passage forming panel and vibration plate

Abstract

An ink jet printhead is provided which includes a head body. The head body includes a passage forming panel formed with a plurality of grooved ink passages each communicating with a discharge port, and a vibration plate laminated on the passage forming panel to face the ink passages. The vibration plate is provided with a plurality of ink inlet ports for introducing ink into the ink passages. Therefore, an ink cartridge may be connected from behind the head body.

We claim: 
     
       1. An inkjet printhead comprising: a head body including a passage forming panel and a vibration plate, the passage forming panel having a first surface formed with a plurality of grooved ink passages and a second surface formed with a corresponding number of discharge ports each communicating with a respective one of the grooved ink passages, the vibration plate being laminated on the first surface of the passage forming panel, the head body being also provided with a plurality of ink inlet ports in communication with the grooved ink passages for introducing ink into the grooved ink passages;   a plurality of piezoelectric elements attached to the vibration plate;   a driver IC electrically connected to the piezoelectric elements for controlling the piezoelectric elements; and   a case member including a front portion for supporting the head body and outer surface portion formed with an inclined groove;   wherein the driver IC is arranged within the inclined groove of the outer surface portion of the case member in a manner such that the driver IC does not project out of the inclined groove.   
     
     
       2. The ink jet printhead according to claim 1, wherein each of the grooved ink passages includes a common ink passage communicating with a respective one of the ink inlet ports, and a plurality of individual ink passages each having one end connected to said each of the common ink passages, said each individual ink passage also having an opposite end being connected to a respective one of the discharge ports. 
     
     
       3. The ink jet printhead according to claim 1, further comprising at least one ink cartridge having an ink outlet port which faces a respective one of the ink inlet ports in communication therewith, the case member being arranged to house the ink cartridge therein and formed with through-holes each arranged in facing relation to a respective one of the ink inlet ports of the head body. 
     
     
       4. The ink jet printhead according to claim 3, further comprising a front frame mounted onto the case member, the front frame having ink supply ports each establishing mutual communication between said respective one of the ink inlet ports and the ink outlet port, each of the ink supply ports of the front frame being provided with a filter for ink filtration. 
     
     
       5. The ink jet printhead according to claim 4, further comprising tubular seals made of an elastic member interposed between the front frame and ink cartridge, the ink outlet port of the ink cartridge being held in communication with one of the ink supply ports of the front frame by one of the tubular seals. 
     
     
       6. The inkjet printhead according to claim 1, further comprising a presser frame for pressing the head body against the front portion of the case member, and a fixing means for fixing the presser frame to the case member. 
     
     
       7. The ink jet printhead according to claim 6, wherein the case member has side surfaces formed with engaging portions, the fixing means comprising engaging pawls provided on the presser frame for engagement with the engaging portions. 
     
     
       8. The ink jet printhead according to claim 3, further comprising annular elastic seals, each of the ink inlet ports and one of the through-holes of the case member being arranged to communicate with each other by one of the annular elastic seals. 
     
     
       9. The ink jet printhead according to claim 3, wherein the ink cartridge is releasably attached to the case member. 
     
     
       10. The ink jet printhead according to claim 1, further comprising a flexible cord for electrically connecting the piezoelectric elements to the driver IC, the driver IC being connected to one end of the flexible cord. 
     
     
       11. The ink jet printhead according to claim 10, further comprising a gap formed between the head body and the case member for taking out a part of the flexible cord onto said outer surface portion of the case member. 
     
     
       12. The ink jet printhead according to claim 10, wherein the driver IC is directly mounted on said one end of the flexible cord. 
     
     
       13. The ink jet printhead according to claim 10, wherein said one end of the flexible cord is provided with terminals for connecting the driver IC to an external printhead control device. 
     
     
       14. The ink jet printhead according to claim 10, further comprising a wiring member provided with terminals for connecting the driver IC to an external printhead control device, said one end of the flexible cord being connected to the wiring member. 
     
     
       15. The ink jet printhead according to claim 10, further comprising a reinforcing plate of a hard material fixed to said one end of the flexible cord. 
     
     
       16. The ink jet printhead according to claim 1, wherein the driver IC is coated with a hard resin. 
     
     
       17. The ink jet printhead according to claim 1, wherein the front portion of the case member is formed with a recess for positioning the head body relative to the case member when the head body is fitted.